Numerous organic bioactives, especially pesticides, i.e., chemicals that are useful in the control of insects, fungi, weeds, and the like have been developed in recent years. Regardless of whether the pesticide is inherently water soluble or water insoluble, it is desirable to use the same in an aqueous medium rather than in a non-aqueous solvent which is more difficult to use by the formulator and applicator, could cause environmental damage, is more costly and is in general, less desirable. Water-based dispersions, emulsions, and/or solutions can be prepared from most pesticides using selected surfactants. Proper selection of the surfactant can also improve the efficacy of pesticidal compositions.
Surfactants have proven to be especially useful in the preparation of herbicidal compositions whether the herbicide is water soluble or insoluble. When the herbicide is water insoluble, the surfactant can be used to make a water dispersible herbicide composition. When the herbicide is water soluble, the surfactant can often be used to improve the herbicidal effectiveness of the herbicidal composition.
One class of surfactants that has found much commercial success in the preparation of herbicidal compositions includes the polyoxyalkylene alkylamines. These compounds have the necessary surface activity so that many otherwise water insoluble herbicides, as well as water soluble herbicides, can be formulated into concentrates which will form useful dispersions, emulsions, and solutions in water. In addition, herbicides formulated into dispersions, emulsions, and solutions using these surfactants often have improved herbicidal properties.
However, while the polyoxyalkylene alkylamine compounds have excellent surfactant properties and often enhance the bioefficacy of phytotoxicants, they unfortunately are irritants, especially producing eye irritation and must be used with a high degree of caution.
Many efforts have been made to reduce the irritancy of the polyoxy alkylene alkylamine compounds while still retaining their surfactant effectiveness in stabilizing agricultural formulations and enhancing bioeffectiveness. Most of these efforts entail the addition of multiple surfactant compounds to the alkylamine--bioactive composition.
Perhaps the most widely used herbicide worldwide is glyphosate, which chemically is N-phosphonomethylglycine. This product is normally used in an agriculturally acceptable form, such as a water soluble salt, e.g., the isopropylamine salt. Often used surfactants for the preparation of glyphosate concentrates, which can then be diluted with water for use by the applicator, are the aforementioned polyoxyalkylene alkylamines, especially the ethoxylated tallow amines.
It is therefore an object of the present invention to provide stable surfactant containing bioactive compositions with enhanced bioeffectiveness.
Another object of the present invention is to provide stable pesticidal compositions, especially herbicidal compositions, and most especially those containing glyphosate, having agriculturally acceptable efficacy and reduced eye irritation.
Another object of the present invention is to provide new methods for controlling the growth of weeds and other vegetation.
Other objects of the present invention will become apparent from the following description.